I don't know if this will help or not, but I was abe to successfuly add forms to my mamblefish site with PerForms (download from
www.joomla.org). Using Performs, I was able to create a version of a form in each language, then publish each one in the content pages of each language. I know it's not an ideal solution, but it's the only way I've found to get forms to work with mamblefish!
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